From cb8e04462f60d3f0659ef3adbba06cdf474f7fe3 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime@cerno.tech>
Date: Mon, 21 Nov 2022 11:11:52 +0100
Subject: [PATCH] drm/tests: helpers: Create the device in another
 function
MIME-Version: 1.0
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We'll need in some tests to control when the device needs to be added
and removed, so let's split the device creation from the DRM device
creation function.

Reviewed-by: Maíra Canal <mcanal@igalia.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
 drivers/gpu/drm/tests/drm_kunit_helpers.c | 56 +++++++++++++----------
 include/drm/drm_kunit_helpers.h           |  5 +-
 2 files changed, 37 insertions(+), 24 deletions(-)

--- a/drivers/gpu/drm/tests/drm_kunit_helpers.c
+++ b/drivers/gpu/drm/tests/drm_kunit_helpers.c
@@ -17,36 +17,51 @@ struct kunit_dev {
 static const struct drm_mode_config_funcs drm_mode_config_funcs = {
 };
 
-static int dev_init(struct kunit_resource *res, void *ptr)
+/**
+ * drm_kunit_helper_alloc_device - Allocate a mock device for a KUnit test
+ * @test: The test context object
+ *
+ * This allocates a fake struct &device to create a mock for a KUnit
+ * test.
+ *
+ * Callers need to make sure drm_kunit_helper_free_device() on the
+ * device when done.
+ *
+ * Returns:
+ * A pointer to the new device, or an ERR_PTR() otherwise.
+ */
+struct device *drm_kunit_helper_alloc_device(struct kunit *test)
 {
-	char *name = ptr;
-	struct device *dev;
-
-	dev = root_device_register(name);
-	if (IS_ERR(dev))
-		return PTR_ERR(dev);
-
-	res->data = dev;
-	return 0;
+	return root_device_register(KUNIT_DEVICE_NAME);
 }
+EXPORT_SYMBOL_GPL(drm_kunit_helper_alloc_device);
 
-static void dev_free(struct kunit_resource *res)
+/**
+ * drm_kunit_helper_free_device - Frees a mock device
+ * @test: The test context object
+ * @dev: The device to free
+ *
+ * Frees a device allocated with drm_kunit_helper_alloc_device().
+ */
+void drm_kunit_helper_free_device(struct kunit *test, struct device *dev)
 {
-	struct device *dev = res->data;
-
 	root_device_unregister(dev);
 }
+EXPORT_SYMBOL_GPL(drm_kunit_helper_free_device);
 
 /**
  * drm_kunit_helper_alloc_drm_device - Allocates a mock DRM device for KUnit tests
  * @test: The test context object
+ * @dev: The parent device object
  * @features: Mocked DRM device driver features
  *
- * This function allocates a new struct &device, creates a struct
- * &drm_driver and will create a struct &drm_device using both.
+ * This function creates a struct &drm_driver and will create a struct
+ * &drm_device from @dev and that driver.
  *
- * The device and driver are tied to the @test context and will get
- * cleaned at the end of the test. The drm_device is allocated through
+ * @dev should be allocated using drm_kunit_helper_alloc_device().
+ *
+ * The driver is tied to the @test context and will get cleaned at the
+ * end of the test. The drm_device is allocated through
  * devm_drm_dev_alloc() and will thus be freed through a device-managed
  * resource.
  *
@@ -54,19 +69,14 @@ static void dev_free(struct kunit_resour
  * A pointer to the new drm_device, or an ERR_PTR() otherwise.
  */
 struct drm_device *
-drm_kunit_helper_alloc_drm_device(struct kunit *test,
+drm_kunit_helper_alloc_drm_device(struct kunit *test, struct device *dev,
 				  u32 features)
 {
 	struct kunit_dev *kdev;
 	struct drm_device *drm;
 	struct drm_driver *driver;
-	struct device *dev;
 	int ret;
 
-	dev = kunit_alloc_resource(test, dev_init, dev_free, GFP_KERNEL, KUNIT_DEVICE_NAME);
-	if (!dev)
-		return ERR_PTR(-ENOMEM);
-
 	driver = kunit_kzalloc(test, sizeof(*driver), GFP_KERNEL);
 	if (!driver)
 		return ERR_PTR(-ENOMEM);
--- a/include/drm/drm_kunit_helpers.h
+++ b/include/drm/drm_kunit_helpers.h
@@ -6,8 +6,11 @@
 struct drm_device;
 struct kunit;
 
+struct device *drm_kunit_helper_alloc_device(struct kunit *test);
+void drm_kunit_helper_free_device(struct kunit *test, struct device *dev);
+
 struct drm_device *
-drm_kunit_helper_alloc_drm_device(struct kunit *test,
+drm_kunit_helper_alloc_drm_device(struct kunit *test, struct device *dev,
 				  u32 features);
 
 #endif // DRM_KUNIT_HELPERS_H_
